xref: /linux/net/compat.c (revision 5051c94bb3998ff24bf07ae3b72dca30f85962f8)
1 /*
2  * 32bit Socket syscall emulation. Based on arch/sparc64/kernel/sys_sparc32.c.
3  *
4  * Copyright (C) 2000		VA Linux Co
5  * Copyright (C) 2000		Don Dugger <n0ano@valinux.com>
6  * Copyright (C) 1999 		Arun Sharma <arun.sharma@intel.com>
7  * Copyright (C) 1997,1998 	Jakub Jelinek (jj@sunsite.mff.cuni.cz)
8  * Copyright (C) 1997 		David S. Miller (davem@caip.rutgers.edu)
9  * Copyright (C) 2000		Hewlett-Packard Co.
10  * Copyright (C) 2000		David Mosberger-Tang <davidm@hpl.hp.com>
11  * Copyright (C) 2000,2001	Andi Kleen, SuSE Labs
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/gfp.h>
16 #include <linux/fs.h>
17 #include <linux/types.h>
18 #include <linux/file.h>
19 #include <linux/icmpv6.h>
20 #include <linux/socket.h>
21 #include <linux/syscalls.h>
22 #include <linux/filter.h>
23 #include <linux/compat.h>
24 #include <linux/security.h>
25 #include <linux/export.h>
26 
27 #include <net/scm.h>
28 #include <net/sock.h>
29 #include <net/ip.h>
30 #include <net/ipv6.h>
31 #include <asm/uaccess.h>
32 #include <net/compat.h>
33 
34 static inline int iov_from_user_compat_to_kern(struct iovec *kiov,
35 					  struct compat_iovec __user *uiov32,
36 					  int niov)
37 {
38 	int tot_len = 0;
39 
40 	while (niov > 0) {
41 		compat_uptr_t buf;
42 		compat_size_t len;
43 
44 		if (get_user(len, &uiov32->iov_len) ||
45 		    get_user(buf, &uiov32->iov_base))
46 			return -EFAULT;
47 
48 		if (len > INT_MAX - tot_len)
49 			len = INT_MAX - tot_len;
50 
51 		tot_len += len;
52 		kiov->iov_base = compat_ptr(buf);
53 		kiov->iov_len = (__kernel_size_t) len;
54 		uiov32++;
55 		kiov++;
56 		niov--;
57 	}
58 	return tot_len;
59 }
60 
61 int get_compat_msghdr(struct msghdr *kmsg, struct compat_msghdr __user *umsg)
62 {
63 	compat_uptr_t tmp1, tmp2, tmp3;
64 
65 	if (!access_ok(VERIFY_READ, umsg, sizeof(*umsg)) ||
66 	    __get_user(tmp1, &umsg->msg_name) ||
67 	    __get_user(kmsg->msg_namelen, &umsg->msg_namelen) ||
68 	    __get_user(tmp2, &umsg->msg_iov) ||
69 	    __get_user(kmsg->msg_iovlen, &umsg->msg_iovlen) ||
70 	    __get_user(tmp3, &umsg->msg_control) ||
71 	    __get_user(kmsg->msg_controllen, &umsg->msg_controllen) ||
72 	    __get_user(kmsg->msg_flags, &umsg->msg_flags))
73 		return -EFAULT;
74 	kmsg->msg_name = compat_ptr(tmp1);
75 	kmsg->msg_iov = compat_ptr(tmp2);
76 	kmsg->msg_control = compat_ptr(tmp3);
77 	return 0;
78 }
79 
80 /* I've named the args so it is easy to tell whose space the pointers are in. */
81 int verify_compat_iovec(struct msghdr *kern_msg, struct iovec *kern_iov,
82 		   struct sockaddr_storage *kern_address, int mode)
83 {
84 	int tot_len;
85 
86 	if (kern_msg->msg_namelen) {
87 		if (mode == VERIFY_READ) {
88 			int err = move_addr_to_kernel(kern_msg->msg_name,
89 						      kern_msg->msg_namelen,
90 						      kern_address);
91 			if (err < 0)
92 				return err;
93 		}
94 		kern_msg->msg_name = kern_address;
95 	} else
96 		kern_msg->msg_name = NULL;
97 
98 	tot_len = iov_from_user_compat_to_kern(kern_iov,
99 					  (struct compat_iovec __user *)kern_msg->msg_iov,
100 					  kern_msg->msg_iovlen);
101 	if (tot_len >= 0)
102 		kern_msg->msg_iov = kern_iov;
103 
104 	return tot_len;
105 }
106 
107 /* Bleech... */
108 #define CMSG_COMPAT_ALIGN(len)	ALIGN((len), sizeof(s32))
109 
110 #define CMSG_COMPAT_DATA(cmsg)				\
111 	((void __user *)((char __user *)(cmsg) + CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr))))
112 #define CMSG_COMPAT_SPACE(len)				\
113 	(CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr)) + CMSG_COMPAT_ALIGN(len))
114 #define CMSG_COMPAT_LEN(len)				\
115 	(CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr)) + (len))
116 
117 #define CMSG_COMPAT_FIRSTHDR(msg)			\
118 	(((msg)->msg_controllen) >= sizeof(struct compat_cmsghdr) ?	\
119 	 (struct compat_cmsghdr __user *)((msg)->msg_control) :		\
120 	 (struct compat_cmsghdr __user *)NULL)
121 
122 #define CMSG_COMPAT_OK(ucmlen, ucmsg, mhdr) \
123 	((ucmlen) >= sizeof(struct compat_cmsghdr) && \
124 	 (ucmlen) <= (unsigned long) \
125 	 ((mhdr)->msg_controllen - \
126 	  ((char *)(ucmsg) - (char *)(mhdr)->msg_control)))
127 
128 static inline struct compat_cmsghdr __user *cmsg_compat_nxthdr(struct msghdr *msg,
129 		struct compat_cmsghdr __user *cmsg, int cmsg_len)
130 {
131 	char __user *ptr = (char __user *)cmsg + CMSG_COMPAT_ALIGN(cmsg_len);
132 	if ((unsigned long)(ptr + 1 - (char __user *)msg->msg_control) >
133 			msg->msg_controllen)
134 		return NULL;
135 	return (struct compat_cmsghdr __user *)ptr;
136 }
137 
138 /* There is a lot of hair here because the alignment rules (and
139  * thus placement) of cmsg headers and length are different for
140  * 32-bit apps.  -DaveM
141  */
142 int cmsghdr_from_user_compat_to_kern(struct msghdr *kmsg, struct sock *sk,
143 			       unsigned char *stackbuf, int stackbuf_size)
144 {
145 	struct compat_cmsghdr __user *ucmsg;
146 	struct cmsghdr *kcmsg, *kcmsg_base;
147 	compat_size_t ucmlen;
148 	__kernel_size_t kcmlen, tmp;
149 	int err = -EFAULT;
150 
151 	kcmlen = 0;
152 	kcmsg_base = kcmsg = (struct cmsghdr *)stackbuf;
153 	ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
154 	while (ucmsg != NULL) {
155 		if (get_user(ucmlen, &ucmsg->cmsg_len))
156 			return -EFAULT;
157 
158 		/* Catch bogons. */
159 		if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
160 			return -EINVAL;
161 
162 		tmp = ((ucmlen - CMSG_COMPAT_ALIGN(sizeof(*ucmsg))) +
163 		       CMSG_ALIGN(sizeof(struct cmsghdr)));
164 		tmp = CMSG_ALIGN(tmp);
165 		kcmlen += tmp;
166 		ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
167 	}
168 	if (kcmlen == 0)
169 		return -EINVAL;
170 
171 	/* The kcmlen holds the 64-bit version of the control length.
172 	 * It may not be modified as we do not stick it into the kmsg
173 	 * until we have successfully copied over all of the data
174 	 * from the user.
175 	 */
176 	if (kcmlen > stackbuf_size)
177 		kcmsg_base = kcmsg = sock_kmalloc(sk, kcmlen, GFP_KERNEL);
178 	if (kcmsg == NULL)
179 		return -ENOBUFS;
180 
181 	/* Now copy them over neatly. */
182 	memset(kcmsg, 0, kcmlen);
183 	ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
184 	while (ucmsg != NULL) {
185 		if (__get_user(ucmlen, &ucmsg->cmsg_len))
186 			goto Efault;
187 		if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
188 			goto Einval;
189 		tmp = ((ucmlen - CMSG_COMPAT_ALIGN(sizeof(*ucmsg))) +
190 		       CMSG_ALIGN(sizeof(struct cmsghdr)));
191 		if ((char *)kcmsg_base + kcmlen - (char *)kcmsg < CMSG_ALIGN(tmp))
192 			goto Einval;
193 		kcmsg->cmsg_len = tmp;
194 		tmp = CMSG_ALIGN(tmp);
195 		if (__get_user(kcmsg->cmsg_level, &ucmsg->cmsg_level) ||
196 		    __get_user(kcmsg->cmsg_type, &ucmsg->cmsg_type) ||
197 		    copy_from_user(CMSG_DATA(kcmsg),
198 				   CMSG_COMPAT_DATA(ucmsg),
199 				   (ucmlen - CMSG_COMPAT_ALIGN(sizeof(*ucmsg)))))
200 			goto Efault;
201 
202 		/* Advance. */
203 		kcmsg = (struct cmsghdr *)((char *)kcmsg + tmp);
204 		ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
205 	}
206 
207 	/* Ok, looks like we made it.  Hook it up and return success. */
208 	kmsg->msg_control = kcmsg_base;
209 	kmsg->msg_controllen = kcmlen;
210 	return 0;
211 
212 Einval:
213 	err = -EINVAL;
214 Efault:
215 	if (kcmsg_base != (struct cmsghdr *)stackbuf)
216 		sock_kfree_s(sk, kcmsg_base, kcmlen);
217 	return err;
218 }
219 
220 int put_cmsg_compat(struct msghdr *kmsg, int level, int type, int len, void *data)
221 {
222 	struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
223 	struct compat_cmsghdr cmhdr;
224 	int cmlen;
225 
226 	if (cm == NULL || kmsg->msg_controllen < sizeof(*cm)) {
227 		kmsg->msg_flags |= MSG_CTRUNC;
228 		return 0; /* XXX: return error? check spec. */
229 	}
230 
231 	if (!COMPAT_USE_64BIT_TIME) {
232 		struct compat_timeval ctv;
233 		struct compat_timespec cts[3];
234 		if (level == SOL_SOCKET && type == SCM_TIMESTAMP) {
235 			struct timeval *tv = (struct timeval *)data;
236 			ctv.tv_sec = tv->tv_sec;
237 			ctv.tv_usec = tv->tv_usec;
238 			data = &ctv;
239 			len = sizeof(ctv);
240 		}
241 		if (level == SOL_SOCKET &&
242 		    (type == SCM_TIMESTAMPNS || type == SCM_TIMESTAMPING)) {
243 			int count = type == SCM_TIMESTAMPNS ? 1 : 3;
244 			int i;
245 			struct timespec *ts = (struct timespec *)data;
246 			for (i = 0; i < count; i++) {
247 				cts[i].tv_sec = ts[i].tv_sec;
248 				cts[i].tv_nsec = ts[i].tv_nsec;
249 			}
250 			data = &cts;
251 			len = sizeof(cts[0]) * count;
252 		}
253 	}
254 
255 	cmlen = CMSG_COMPAT_LEN(len);
256 	if (kmsg->msg_controllen < cmlen) {
257 		kmsg->msg_flags |= MSG_CTRUNC;
258 		cmlen = kmsg->msg_controllen;
259 	}
260 	cmhdr.cmsg_level = level;
261 	cmhdr.cmsg_type = type;
262 	cmhdr.cmsg_len = cmlen;
263 
264 	if (copy_to_user(cm, &cmhdr, sizeof cmhdr))
265 		return -EFAULT;
266 	if (copy_to_user(CMSG_COMPAT_DATA(cm), data, cmlen - sizeof(struct compat_cmsghdr)))
267 		return -EFAULT;
268 	cmlen = CMSG_COMPAT_SPACE(len);
269 	if (kmsg->msg_controllen < cmlen)
270 		cmlen = kmsg->msg_controllen;
271 	kmsg->msg_control += cmlen;
272 	kmsg->msg_controllen -= cmlen;
273 	return 0;
274 }
275 
276 void scm_detach_fds_compat(struct msghdr *kmsg, struct scm_cookie *scm)
277 {
278 	struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
279 	int fdmax = (kmsg->msg_controllen - sizeof(struct compat_cmsghdr)) / sizeof(int);
280 	int fdnum = scm->fp->count;
281 	struct file **fp = scm->fp->fp;
282 	int __user *cmfptr;
283 	int err = 0, i;
284 
285 	if (fdnum < fdmax)
286 		fdmax = fdnum;
287 
288 	for (i = 0, cmfptr = (int __user *) CMSG_COMPAT_DATA(cm); i < fdmax; i++, cmfptr++) {
289 		int new_fd;
290 		err = security_file_receive(fp[i]);
291 		if (err)
292 			break;
293 		err = get_unused_fd_flags(MSG_CMSG_CLOEXEC & kmsg->msg_flags
294 					  ? O_CLOEXEC : 0);
295 		if (err < 0)
296 			break;
297 		new_fd = err;
298 		err = put_user(new_fd, cmfptr);
299 		if (err) {
300 			put_unused_fd(new_fd);
301 			break;
302 		}
303 		/* Bump the usage count and install the file. */
304 		get_file(fp[i]);
305 		fd_install(new_fd, fp[i]);
306 	}
307 
308 	if (i > 0) {
309 		int cmlen = CMSG_COMPAT_LEN(i * sizeof(int));
310 		err = put_user(SOL_SOCKET, &cm->cmsg_level);
311 		if (!err)
312 			err = put_user(SCM_RIGHTS, &cm->cmsg_type);
313 		if (!err)
314 			err = put_user(cmlen, &cm->cmsg_len);
315 		if (!err) {
316 			cmlen = CMSG_COMPAT_SPACE(i * sizeof(int));
317 			kmsg->msg_control += cmlen;
318 			kmsg->msg_controllen -= cmlen;
319 		}
320 	}
321 	if (i < fdnum)
322 		kmsg->msg_flags |= MSG_CTRUNC;
323 
324 	/*
325 	 * All of the files that fit in the message have had their
326 	 * usage counts incremented, so we just free the list.
327 	 */
328 	__scm_destroy(scm);
329 }
330 
331 static int do_set_attach_filter(struct socket *sock, int level, int optname,
332 				char __user *optval, unsigned int optlen)
333 {
334 	struct compat_sock_fprog __user *fprog32 = (struct compat_sock_fprog __user *)optval;
335 	struct sock_fprog __user *kfprog = compat_alloc_user_space(sizeof(struct sock_fprog));
336 	compat_uptr_t ptr;
337 	u16 len;
338 
339 	if (!access_ok(VERIFY_READ, fprog32, sizeof(*fprog32)) ||
340 	    !access_ok(VERIFY_WRITE, kfprog, sizeof(struct sock_fprog)) ||
341 	    __get_user(len, &fprog32->len) ||
342 	    __get_user(ptr, &fprog32->filter) ||
343 	    __put_user(len, &kfprog->len) ||
344 	    __put_user(compat_ptr(ptr), &kfprog->filter))
345 		return -EFAULT;
346 
347 	return sock_setsockopt(sock, level, optname, (char __user *)kfprog,
348 			      sizeof(struct sock_fprog));
349 }
350 
351 static int do_set_sock_timeout(struct socket *sock, int level,
352 		int optname, char __user *optval, unsigned int optlen)
353 {
354 	struct compat_timeval __user *up = (struct compat_timeval __user *)optval;
355 	struct timeval ktime;
356 	mm_segment_t old_fs;
357 	int err;
358 
359 	if (optlen < sizeof(*up))
360 		return -EINVAL;
361 	if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
362 	    __get_user(ktime.tv_sec, &up->tv_sec) ||
363 	    __get_user(ktime.tv_usec, &up->tv_usec))
364 		return -EFAULT;
365 	old_fs = get_fs();
366 	set_fs(KERNEL_DS);
367 	err = sock_setsockopt(sock, level, optname, (char *)&ktime, sizeof(ktime));
368 	set_fs(old_fs);
369 
370 	return err;
371 }
372 
373 static int compat_sock_setsockopt(struct socket *sock, int level, int optname,
374 				char __user *optval, unsigned int optlen)
375 {
376 	if (optname == SO_ATTACH_FILTER)
377 		return do_set_attach_filter(sock, level, optname,
378 					    optval, optlen);
379 	if (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO)
380 		return do_set_sock_timeout(sock, level, optname, optval, optlen);
381 
382 	return sock_setsockopt(sock, level, optname, optval, optlen);
383 }
384 
385 asmlinkage long compat_sys_setsockopt(int fd, int level, int optname,
386 				char __user *optval, unsigned int optlen)
387 {
388 	int err;
389 	struct socket *sock = sockfd_lookup(fd, &err);
390 
391 	if (sock) {
392 		err = security_socket_setsockopt(sock, level, optname);
393 		if (err) {
394 			sockfd_put(sock);
395 			return err;
396 		}
397 
398 		if (level == SOL_SOCKET)
399 			err = compat_sock_setsockopt(sock, level,
400 					optname, optval, optlen);
401 		else if (sock->ops->compat_setsockopt)
402 			err = sock->ops->compat_setsockopt(sock, level,
403 					optname, optval, optlen);
404 		else
405 			err = sock->ops->setsockopt(sock, level,
406 					optname, optval, optlen);
407 		sockfd_put(sock);
408 	}
409 	return err;
410 }
411 
412 static int do_get_sock_timeout(struct socket *sock, int level, int optname,
413 		char __user *optval, int __user *optlen)
414 {
415 	struct compat_timeval __user *up;
416 	struct timeval ktime;
417 	mm_segment_t old_fs;
418 	int len, err;
419 
420 	up = (struct compat_timeval __user *) optval;
421 	if (get_user(len, optlen))
422 		return -EFAULT;
423 	if (len < sizeof(*up))
424 		return -EINVAL;
425 	len = sizeof(ktime);
426 	old_fs = get_fs();
427 	set_fs(KERNEL_DS);
428 	err = sock_getsockopt(sock, level, optname, (char *) &ktime, &len);
429 	set_fs(old_fs);
430 
431 	if (!err) {
432 		if (put_user(sizeof(*up), optlen) ||
433 		    !access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
434 		    __put_user(ktime.tv_sec, &up->tv_sec) ||
435 		    __put_user(ktime.tv_usec, &up->tv_usec))
436 			err = -EFAULT;
437 	}
438 	return err;
439 }
440 
441 static int compat_sock_getsockopt(struct socket *sock, int level, int optname,
442 				char __user *optval, int __user *optlen)
443 {
444 	if (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO)
445 		return do_get_sock_timeout(sock, level, optname, optval, optlen);
446 	return sock_getsockopt(sock, level, optname, optval, optlen);
447 }
448 
449 int compat_sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
450 {
451 	struct compat_timeval __user *ctv;
452 	int err;
453 	struct timeval tv;
454 
455 	if (COMPAT_USE_64BIT_TIME)
456 		return sock_get_timestamp(sk, userstamp);
457 
458 	ctv = (struct compat_timeval __user *) userstamp;
459 	err = -ENOENT;
460 	if (!sock_flag(sk, SOCK_TIMESTAMP))
461 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
462 	tv = ktime_to_timeval(sk->sk_stamp);
463 	if (tv.tv_sec == -1)
464 		return err;
465 	if (tv.tv_sec == 0) {
466 		sk->sk_stamp = ktime_get_real();
467 		tv = ktime_to_timeval(sk->sk_stamp);
468 	}
469 	err = 0;
470 	if (put_user(tv.tv_sec, &ctv->tv_sec) ||
471 			put_user(tv.tv_usec, &ctv->tv_usec))
472 		err = -EFAULT;
473 	return err;
474 }
475 EXPORT_SYMBOL(compat_sock_get_timestamp);
476 
477 int compat_sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
478 {
479 	struct compat_timespec __user *ctv;
480 	int err;
481 	struct timespec ts;
482 
483 	if (COMPAT_USE_64BIT_TIME)
484 		return sock_get_timestampns (sk, userstamp);
485 
486 	ctv = (struct compat_timespec __user *) userstamp;
487 	err = -ENOENT;
488 	if (!sock_flag(sk, SOCK_TIMESTAMP))
489 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
490 	ts = ktime_to_timespec(sk->sk_stamp);
491 	if (ts.tv_sec == -1)
492 		return err;
493 	if (ts.tv_sec == 0) {
494 		sk->sk_stamp = ktime_get_real();
495 		ts = ktime_to_timespec(sk->sk_stamp);
496 	}
497 	err = 0;
498 	if (put_user(ts.tv_sec, &ctv->tv_sec) ||
499 			put_user(ts.tv_nsec, &ctv->tv_nsec))
500 		err = -EFAULT;
501 	return err;
502 }
503 EXPORT_SYMBOL(compat_sock_get_timestampns);
504 
505 asmlinkage long compat_sys_getsockopt(int fd, int level, int optname,
506 				char __user *optval, int __user *optlen)
507 {
508 	int err;
509 	struct socket *sock = sockfd_lookup(fd, &err);
510 
511 	if (sock) {
512 		err = security_socket_getsockopt(sock, level, optname);
513 		if (err) {
514 			sockfd_put(sock);
515 			return err;
516 		}
517 
518 		if (level == SOL_SOCKET)
519 			err = compat_sock_getsockopt(sock, level,
520 					optname, optval, optlen);
521 		else if (sock->ops->compat_getsockopt)
522 			err = sock->ops->compat_getsockopt(sock, level,
523 					optname, optval, optlen);
524 		else
525 			err = sock->ops->getsockopt(sock, level,
526 					optname, optval, optlen);
527 		sockfd_put(sock);
528 	}
529 	return err;
530 }
531 
532 struct compat_group_req {
533 	__u32				 gr_interface;
534 	struct __kernel_sockaddr_storage gr_group
535 		__attribute__ ((aligned(4)));
536 } __packed;
537 
538 struct compat_group_source_req {
539 	__u32				 gsr_interface;
540 	struct __kernel_sockaddr_storage gsr_group
541 		__attribute__ ((aligned(4)));
542 	struct __kernel_sockaddr_storage gsr_source
543 		__attribute__ ((aligned(4)));
544 } __packed;
545 
546 struct compat_group_filter {
547 	__u32				 gf_interface;
548 	struct __kernel_sockaddr_storage gf_group
549 		__attribute__ ((aligned(4)));
550 	__u32				 gf_fmode;
551 	__u32				 gf_numsrc;
552 	struct __kernel_sockaddr_storage gf_slist[1]
553 		__attribute__ ((aligned(4)));
554 } __packed;
555 
556 #define __COMPAT_GF0_SIZE (sizeof(struct compat_group_filter) - \
557 			sizeof(struct __kernel_sockaddr_storage))
558 
559 
560 int compat_mc_setsockopt(struct sock *sock, int level, int optname,
561 	char __user *optval, unsigned int optlen,
562 	int (*setsockopt)(struct sock *, int, int, char __user *, unsigned int))
563 {
564 	char __user	*koptval = optval;
565 	int		koptlen = optlen;
566 
567 	switch (optname) {
568 	case MCAST_JOIN_GROUP:
569 	case MCAST_LEAVE_GROUP:
570 	{
571 		struct compat_group_req __user *gr32 = (void *)optval;
572 		struct group_req __user *kgr =
573 			compat_alloc_user_space(sizeof(struct group_req));
574 		u32 interface;
575 
576 		if (!access_ok(VERIFY_READ, gr32, sizeof(*gr32)) ||
577 		    !access_ok(VERIFY_WRITE, kgr, sizeof(struct group_req)) ||
578 		    __get_user(interface, &gr32->gr_interface) ||
579 		    __put_user(interface, &kgr->gr_interface) ||
580 		    copy_in_user(&kgr->gr_group, &gr32->gr_group,
581 				sizeof(kgr->gr_group)))
582 			return -EFAULT;
583 		koptval = (char __user *)kgr;
584 		koptlen = sizeof(struct group_req);
585 		break;
586 	}
587 	case MCAST_JOIN_SOURCE_GROUP:
588 	case MCAST_LEAVE_SOURCE_GROUP:
589 	case MCAST_BLOCK_SOURCE:
590 	case MCAST_UNBLOCK_SOURCE:
591 	{
592 		struct compat_group_source_req __user *gsr32 = (void *)optval;
593 		struct group_source_req __user *kgsr = compat_alloc_user_space(
594 			sizeof(struct group_source_req));
595 		u32 interface;
596 
597 		if (!access_ok(VERIFY_READ, gsr32, sizeof(*gsr32)) ||
598 		    !access_ok(VERIFY_WRITE, kgsr,
599 			sizeof(struct group_source_req)) ||
600 		    __get_user(interface, &gsr32->gsr_interface) ||
601 		    __put_user(interface, &kgsr->gsr_interface) ||
602 		    copy_in_user(&kgsr->gsr_group, &gsr32->gsr_group,
603 				sizeof(kgsr->gsr_group)) ||
604 		    copy_in_user(&kgsr->gsr_source, &gsr32->gsr_source,
605 				sizeof(kgsr->gsr_source)))
606 			return -EFAULT;
607 		koptval = (char __user *)kgsr;
608 		koptlen = sizeof(struct group_source_req);
609 		break;
610 	}
611 	case MCAST_MSFILTER:
612 	{
613 		struct compat_group_filter __user *gf32 = (void *)optval;
614 		struct group_filter __user *kgf;
615 		u32 interface, fmode, numsrc;
616 
617 		if (!access_ok(VERIFY_READ, gf32, __COMPAT_GF0_SIZE) ||
618 		    __get_user(interface, &gf32->gf_interface) ||
619 		    __get_user(fmode, &gf32->gf_fmode) ||
620 		    __get_user(numsrc, &gf32->gf_numsrc))
621 			return -EFAULT;
622 		koptlen = optlen + sizeof(struct group_filter) -
623 				sizeof(struct compat_group_filter);
624 		if (koptlen < GROUP_FILTER_SIZE(numsrc))
625 			return -EINVAL;
626 		kgf = compat_alloc_user_space(koptlen);
627 		if (!access_ok(VERIFY_WRITE, kgf, koptlen) ||
628 		    __put_user(interface, &kgf->gf_interface) ||
629 		    __put_user(fmode, &kgf->gf_fmode) ||
630 		    __put_user(numsrc, &kgf->gf_numsrc) ||
631 		    copy_in_user(&kgf->gf_group, &gf32->gf_group,
632 				sizeof(kgf->gf_group)) ||
633 		    (numsrc && copy_in_user(kgf->gf_slist, gf32->gf_slist,
634 				numsrc * sizeof(kgf->gf_slist[0]))))
635 			return -EFAULT;
636 		koptval = (char __user *)kgf;
637 		break;
638 	}
639 
640 	default:
641 		break;
642 	}
643 	return setsockopt(sock, level, optname, koptval, koptlen);
644 }
645 EXPORT_SYMBOL(compat_mc_setsockopt);
646 
647 int compat_mc_getsockopt(struct sock *sock, int level, int optname,
648 	char __user *optval, int __user *optlen,
649 	int (*getsockopt)(struct sock *, int, int, char __user *, int __user *))
650 {
651 	struct compat_group_filter __user *gf32 = (void *)optval;
652 	struct group_filter __user *kgf;
653 	int __user	*koptlen;
654 	u32 interface, fmode, numsrc;
655 	int klen, ulen, err;
656 
657 	if (optname != MCAST_MSFILTER)
658 		return getsockopt(sock, level, optname, optval, optlen);
659 
660 	koptlen = compat_alloc_user_space(sizeof(*koptlen));
661 	if (!access_ok(VERIFY_READ, optlen, sizeof(*optlen)) ||
662 	    __get_user(ulen, optlen))
663 		return -EFAULT;
664 
665 	/* adjust len for pad */
666 	klen = ulen + sizeof(*kgf) - sizeof(*gf32);
667 
668 	if (klen < GROUP_FILTER_SIZE(0))
669 		return -EINVAL;
670 
671 	if (!access_ok(VERIFY_WRITE, koptlen, sizeof(*koptlen)) ||
672 	    __put_user(klen, koptlen))
673 		return -EFAULT;
674 
675 	/* have to allow space for previous compat_alloc_user_space, too */
676 	kgf = compat_alloc_user_space(klen+sizeof(*optlen));
677 
678 	if (!access_ok(VERIFY_READ, gf32, __COMPAT_GF0_SIZE) ||
679 	    __get_user(interface, &gf32->gf_interface) ||
680 	    __get_user(fmode, &gf32->gf_fmode) ||
681 	    __get_user(numsrc, &gf32->gf_numsrc) ||
682 	    __put_user(interface, &kgf->gf_interface) ||
683 	    __put_user(fmode, &kgf->gf_fmode) ||
684 	    __put_user(numsrc, &kgf->gf_numsrc) ||
685 	    copy_in_user(&kgf->gf_group, &gf32->gf_group, sizeof(kgf->gf_group)))
686 		return -EFAULT;
687 
688 	err = getsockopt(sock, level, optname, (char __user *)kgf, koptlen);
689 	if (err)
690 		return err;
691 
692 	if (!access_ok(VERIFY_READ, koptlen, sizeof(*koptlen)) ||
693 	    __get_user(klen, koptlen))
694 		return -EFAULT;
695 
696 	ulen = klen - (sizeof(*kgf)-sizeof(*gf32));
697 
698 	if (!access_ok(VERIFY_WRITE, optlen, sizeof(*optlen)) ||
699 	    __put_user(ulen, optlen))
700 		return -EFAULT;
701 
702 	if (!access_ok(VERIFY_READ, kgf, klen) ||
703 	    !access_ok(VERIFY_WRITE, gf32, ulen) ||
704 	    __get_user(interface, &kgf->gf_interface) ||
705 	    __get_user(fmode, &kgf->gf_fmode) ||
706 	    __get_user(numsrc, &kgf->gf_numsrc) ||
707 	    __put_user(interface, &gf32->gf_interface) ||
708 	    __put_user(fmode, &gf32->gf_fmode) ||
709 	    __put_user(numsrc, &gf32->gf_numsrc))
710 		return -EFAULT;
711 	if (numsrc) {
712 		int copylen;
713 
714 		klen -= GROUP_FILTER_SIZE(0);
715 		copylen = numsrc * sizeof(gf32->gf_slist[0]);
716 		if (copylen > klen)
717 			copylen = klen;
718 		if (copy_in_user(gf32->gf_slist, kgf->gf_slist, copylen))
719 			return -EFAULT;
720 	}
721 	return err;
722 }
723 EXPORT_SYMBOL(compat_mc_getsockopt);
724 
725 
726 /* Argument list sizes for compat_sys_socketcall */
727 #define AL(x) ((x) * sizeof(u32))
728 static unsigned char nas[21] = {
729 	AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
730 	AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
731 	AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
732 	AL(4), AL(5), AL(4)
733 };
734 #undef AL
735 
736 asmlinkage long compat_sys_sendmsg(int fd, struct compat_msghdr __user *msg, unsigned int flags)
737 {
738 	return sys_sendmsg(fd, (struct msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
739 }
740 
741 asmlinkage long compat_sys_sendmmsg(int fd, struct compat_mmsghdr __user *mmsg,
742 				    unsigned int vlen, unsigned int flags)
743 {
744 	return __sys_sendmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
745 			      flags | MSG_CMSG_COMPAT);
746 }
747 
748 asmlinkage long compat_sys_recvmsg(int fd, struct compat_msghdr __user *msg, unsigned int flags)
749 {
750 	return sys_recvmsg(fd, (struct msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
751 }
752 
753 asmlinkage long compat_sys_recv(int fd, void __user *buf, size_t len, unsigned int flags)
754 {
755 	return sys_recv(fd, buf, len, flags | MSG_CMSG_COMPAT);
756 }
757 
758 asmlinkage long compat_sys_recvfrom(int fd, void __user *buf, size_t len,
759 				    unsigned int flags, struct sockaddr __user *addr,
760 				    int __user *addrlen)
761 {
762 	return sys_recvfrom(fd, buf, len, flags | MSG_CMSG_COMPAT, addr, addrlen);
763 }
764 
765 asmlinkage long compat_sys_recvmmsg(int fd, struct compat_mmsghdr __user *mmsg,
766 				    unsigned int vlen, unsigned int flags,
767 				    struct compat_timespec __user *timeout)
768 {
769 	int datagrams;
770 	struct timespec ktspec;
771 
772 	if (COMPAT_USE_64BIT_TIME)
773 		return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
774 				      flags | MSG_CMSG_COMPAT,
775 				      (struct timespec *) timeout);
776 
777 	if (timeout == NULL)
778 		return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
779 				      flags | MSG_CMSG_COMPAT, NULL);
780 
781 	if (get_compat_timespec(&ktspec, timeout))
782 		return -EFAULT;
783 
784 	datagrams = __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
785 				   flags | MSG_CMSG_COMPAT, &ktspec);
786 	if (datagrams > 0 && put_compat_timespec(&ktspec, timeout))
787 		datagrams = -EFAULT;
788 
789 	return datagrams;
790 }
791 
792 asmlinkage long compat_sys_socketcall(int call, u32 __user *args)
793 {
794 	int ret;
795 	u32 a[6];
796 	u32 a0, a1;
797 
798 	if (call < SYS_SOCKET || call > SYS_SENDMMSG)
799 		return -EINVAL;
800 	if (copy_from_user(a, args, nas[call]))
801 		return -EFAULT;
802 	a0 = a[0];
803 	a1 = a[1];
804 
805 	switch (call) {
806 	case SYS_SOCKET:
807 		ret = sys_socket(a0, a1, a[2]);
808 		break;
809 	case SYS_BIND:
810 		ret = sys_bind(a0, compat_ptr(a1), a[2]);
811 		break;
812 	case SYS_CONNECT:
813 		ret = sys_connect(a0, compat_ptr(a1), a[2]);
814 		break;
815 	case SYS_LISTEN:
816 		ret = sys_listen(a0, a1);
817 		break;
818 	case SYS_ACCEPT:
819 		ret = sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), 0);
820 		break;
821 	case SYS_GETSOCKNAME:
822 		ret = sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2]));
823 		break;
824 	case SYS_GETPEERNAME:
825 		ret = sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2]));
826 		break;
827 	case SYS_SOCKETPAIR:
828 		ret = sys_socketpair(a0, a1, a[2], compat_ptr(a[3]));
829 		break;
830 	case SYS_SEND:
831 		ret = sys_send(a0, compat_ptr(a1), a[2], a[3]);
832 		break;
833 	case SYS_SENDTO:
834 		ret = sys_sendto(a0, compat_ptr(a1), a[2], a[3], compat_ptr(a[4]), a[5]);
835 		break;
836 	case SYS_RECV:
837 		ret = compat_sys_recv(a0, compat_ptr(a1), a[2], a[3]);
838 		break;
839 	case SYS_RECVFROM:
840 		ret = compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
841 					  compat_ptr(a[4]), compat_ptr(a[5]));
842 		break;
843 	case SYS_SHUTDOWN:
844 		ret = sys_shutdown(a0, a1);
845 		break;
846 	case SYS_SETSOCKOPT:
847 		ret = compat_sys_setsockopt(a0, a1, a[2],
848 				compat_ptr(a[3]), a[4]);
849 		break;
850 	case SYS_GETSOCKOPT:
851 		ret = compat_sys_getsockopt(a0, a1, a[2],
852 				compat_ptr(a[3]), compat_ptr(a[4]));
853 		break;
854 	case SYS_SENDMSG:
855 		ret = compat_sys_sendmsg(a0, compat_ptr(a1), a[2]);
856 		break;
857 	case SYS_SENDMMSG:
858 		ret = compat_sys_sendmmsg(a0, compat_ptr(a1), a[2], a[3]);
859 		break;
860 	case SYS_RECVMSG:
861 		ret = compat_sys_recvmsg(a0, compat_ptr(a1), a[2]);
862 		break;
863 	case SYS_RECVMMSG:
864 		ret = compat_sys_recvmmsg(a0, compat_ptr(a1), a[2], a[3],
865 					  compat_ptr(a[4]));
866 		break;
867 	case SYS_ACCEPT4:
868 		ret = sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), a[3]);
869 		break;
870 	default:
871 		ret = -EINVAL;
872 		break;
873 	}
874 	return ret;
875 }
876